NEW YORK (AP) While the new Will Smith film ''Concussion'' may lead some to question their support of the NFL, the forensic pathologist who first drew attention to the dangers of repeated head trauma said he wanted his discoveries to ''advance football.''

''Concussion'' tells the true story of Dr. Bennet Omalu who stumbled upon an insidious brain disorder affecting football players that began in 2002 with an autopsy on former Pittsburgh Steelers center Mike Webster.

''I had this hunger in me to use my knowledge to become a voice for the voiceless, to make a difference, just like Will Smith,'' Omalu said.

Smith said the script enlightened him about the dangerous effects of multiple concussions.

''When I met Bennet and went through the science, I was terrified as a parent,'' Smith said. ''My son played football for four years and I had no idea this was an issue.''

Omalu studied the brains of NFL players who had died under dubious circumstances, including former NFL players Justin Strzelczyk, Terry Long, and Andre Waters, who are depicted in the film. Strzelczyk was involved in a head-on collision on the wrong side of the highway evading police; Waters shot himself in the head; and Terry Long died from drinking anti-freeze.

His study, in conjunction with the University of Pittsburgh's pathology department, led to the discovery that the former players were suffering from Chronic Traumatic Encephalopathy, or CTE, an asymptomatic brain disease. The effects of the incurable disease don't show up until later in life and manifest as psychotic episodes, dementia, and suicide.

CTE had been researched previously in boxers and it had been identified in soccer and rugby players, though Omalu's work first linked it to American football players and has sparked broad discussions about player safety.

After researching the role and learning more about the condition, Smith remains a football fan. Yet, he feels different about the game.

''I wanted to be a part of it just to deliver information to parents and to players because if I didn't know, I felt a lot of other people didn't know,'' Smith said.

David Morse, who plays Webster in the film, found the role a challenge.

''(Mike Webster) was adored by people, the city of Pittsburgh, but what we see is a man at the end of his life with dementia,'' Morse said. ''He's gluing his teeth in with Super Glue, tasering himself. He's just in a kind of hell at the end of his life.''

Webster's problems progressed after his 1997 induction into the Pro Football Hall of Fame. He went on a downward spiral, dying in 2002 at age 50.

Morse admits playing Webster affected him.

''I'm fascinated by the game, but I can't watch it the same way,'' he said. ''I still watch it, but I understand way more about what's happening to these people on the field.''

The NFL attacked the study, and the Nigerian-born Omalu feared deportation. But he kept his resolve.

''My faith made me not afraid,'' Omalu said. ''Americans are perfect and seek perfection in whatever they do, so I was simply being American to contribute my part to this wonderful country, to actually advance football.''

Morse sees that era as a dark period for professional football.

''The NFL at that time period should not look good. They were doing the wrong thing. they were trying to crush anybody, Dr. Omalu, who wanted to talk about it,'' he said. ''Now, they starting to do the right thing and thank goodness they are.

''Nobody wants the game to go away, but there needs to be an awareness and an honesty with players and parents of young children playing the game,'' Morse said.


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